Kinetics and catalysis of oxidation of phenol by ruthenium(IV)–oxo complex

Kinetics of oxidation of phenol by [RuIV(tpy)(pic)(O)]+ (tpy = 2,2′,6′,2″-terpyridine; pic− = picolinate) (1) has been studied in aqueous solution using a rapid scan stopped-flow spectrophotometer. Under pseudo-first order conditions of excess phenol concentrations, the rate of reaction was found to be first order in respect to both 1 and phenol concentrations. Quinones and [RuII(tpy)(pic)(H2O)]+ (2) were found to be the ultimate products of the reaction. Kinetic results were analyzed by using global kinetic analysis techniques and a working mechanism in agreement with the rate and activation parameters is presented. The experimental results are discussed in reference to data reported for the phenol oxidation by relevant RuIVO systems. Catalytic ability of 2 in effecting phenol oxidation in the presence of t-BuOOH has been explored.

Stopped-flow kinetic studies and SPECFIT global kinetic analysis revealed the presence of two steps in the oxidation of phenol to quinone by [RuIV(tpy)(pic)(O)]+ in H2O. Figure optionsDownload as PowerPoint slide